A novel method is proposed to enhance the gasification and removal of copper from molten steel by adding ammonium salts or urea into molten steel under normal pressure.The decopperization experiments were conducted in...A novel method is proposed to enhance the gasification and removal of copper from molten steel by adding ammonium salts or urea into molten steel under normal pressure.The decopperization experiments were conducted in a molybdenum-wire resistance furnace at 1 873 K.The copper content of about 400 g of a mild steel was reduced from 0.49%(mass fraction,the same below) and 0.51% to 0.31% and 0.38% using 0.7 g of NHC1 and 0.5 g of(NH)COrespectively,while the copper content of the molten steel was reduced from 0.61%to 0.56% using 2.00 g of NHCONH.展开更多
In this study,for the first time,direct copper production from copper sulfide was carried out via direct electrochemical reduction method using inexpensive and stable molten borax electrolyte.The effects of current de...In this study,for the first time,direct copper production from copper sulfide was carried out via direct electrochemical reduction method using inexpensive and stable molten borax electrolyte.The effects of current density(100–800 mA/cm^2)and electrolysis time(15–90 min)on both the cathodic current efficiency and copper yield were systematically investigated in consideration of possible electrochemical/chemical reactions at 1200℃.The copper production yield reached 98.09%after 90 min of electrolysis at a current density of 600 mA/cm^2.Direct metal production was shown to be possible with 6 kWh/kg energy consumption at a 600 mA/cm2 current density,at which the highest current efficiency(41%)was obtained.The suggested method can also be applied to metal/alloy production from single-and mixed-metal sulfides coming from primary production and precipitated sulfides,which are produced in the mining and metallurgical industries during treatment of process solutions or wastewaters.展开更多
A novel method has been proposed to remove copper from molten steel by adding the compounds of hydrogen and nitrogen into the melt at normal pressure. Feasibility experiments were carried out in Mo-wire resistance fur...A novel method has been proposed to remove copper from molten steel by adding the compounds of hydrogen and nitrogen into the melt at normal pressure. Feasibility experiments were carried out in Mo-wire resistance furnace at 1600℃. The copper content of about 400 g 45 steel were reduced from 0.60% and 0.57% to 0.41% and 0.51% with 3.25g and 1.20 g NH_4Cl respectively, while the copper contents of about 300 g steel melt were reduced from 1.15% and 0.61% to 0.90% and 0.56% with 4.10 g and 2.00 g NH_2CONH_2. These results indicate that the proposed method is very promising to be put into practical and worthwhile of further study.展开更多
The electrochemical behaviour of copper electrode in molten NaCl-KCl-LaCl_3 has been investigated.The La-Cu alloy is formed at first and then the metallic lanthanum is deposited when the La^(3+)is reduced on the coppe...The electrochemical behaviour of copper electrode in molten NaCl-KCl-LaCl_3 has been investigated.The La-Cu alloy is formed at first and then the metallic lanthanum is deposited when the La^(3+)is reduced on the copper electrode.The technological conditions of preparing La-Cu alloy by consumable cathode have been dis- cussed.The La-Cu alloy contained lanthanum over 90wt% was obtained.The composition of alloy was LaCu_2 and La.The current efficiency was 85% and the recovery of lanthanum was near 90%.展开更多
The electrochemical behaviour of Y ̄(3+) and Ba ̄(2+) on platinum and copper electrode in molten YF_3(70 wt% )-NaF (20 wt%)-CaF_2(10 wt%) has been studied by means of cyclic voltammetry. discharge curve and so on. Th...The electrochemical behaviour of Y ̄(3+) and Ba ̄(2+) on platinum and copper electrode in molten YF_3(70 wt% )-NaF (20 wt%)-CaF_2(10 wt%) has been studied by means of cyclic voltammetry. discharge curve and so on. The Y-Ba-Cu alloy is obtained by fused salt electrolysis with molten YF_3-NaF-CaF_2 as electrolyte and Y_2O_3 and BaO as raw materials. Graphite cell acted as an anode and copper rod as consumable cathode. The molten bath temperature was 1193 K. Cathode current density was 20 A/cm ̄2. The contents of yttrium, barium and copper in alloy were about 20wt%, 9 wt% and 71 wt% respectively. Yttrium recovery efficiency was 90 wt%. The current efficiency was 70%~80 %.展开更多
The copper contents and its existing forms in the slags during the slag-making stage of Peirce-Smith converters in Guixi Smelter, Jiangxi Province, China have been investigated. The investigation was based on plant tr...The copper contents and its existing forms in the slags during the slag-making stage of Peirce-Smith converters in Guixi Smelter, Jiangxi Province, China have been investigated. The investigation was based on plant trials with the corresponding thermodynamic calculations and kinetic considerations. From the plant data, the total copper content in the slags was in the range of 2% to 8% (mass fraction). The mechanical entrainment of matte drops has been found to be the main cause of the copper loss. The suspension index, defined as the ratio of the mass fraction of copper in suspended matte drops in the slag to that in bulk of the matte phase, has been adopted to quantify the matte entrainment. The values of this parameter estimated in this work have been found mainly within a range of 2.5%-8.0%. The Fe3O4 content in the slag has been estimated to be the most important factor, among others, influencing the separation of slag with matte and, consequently, the copper loss from the slag.展开更多
Solid liquid extraction of copper ion (I) with 2, 9-dimethyl-1, 10-phenanthroline (neo-cuproine, DMP) into molten naphthalene followed by chloroform spectrophotometric determination has been studied experimentally. Th...Solid liquid extraction of copper ion (I) with 2, 9-dimethyl-1, 10-phenanthroline (neo-cuproine, DMP) into molten naphthalene followed by chloroform spectrophotometric determination has been studied experimentally. The ternary complex Cu(I)-DMP-ClO4 was extracted quantitatively into molten naphthalene in the range of pH from 5 to 6 at 85 C-. Absorbance was spectrophotometrically determined at 459 nm against the reagent blank after the solid naphthalene layer was anhydrously dissolved in chloroform. Beer's law is obeyed over a concentration range of 0.5-70 mug/mL. The molar absorptivity and Sandell's sensitivity are 1.0x10(4) L/(mol(.)cm) and 0.0099 mug(.)cm(2) respectively. In addition, the various conditions on determination and the interference of coexisted ions were discussed, and the method was applied to the determination of copper ion both in tea samples and cadmium sulfate reagents. The results are in good agreement with those obtained by ICP AES method.展开更多
The electrolytic production of nickel-copper alloy by electrochemical reduction of converter matte in molten salt has been investigated. The sintered solid porous pellets of Ni3S2, Cu2S and converter matte were electr...The electrolytic production of nickel-copper alloy by electrochemical reduction of converter matte in molten salt has been investigated. The sintered solid porous pellets of Ni3S2, Cu2S and converter matte were electrolyzed at a voltage of 3.0 V in molten CaCl2-NaCl under the protection of argon gas at 700℃, respectively. The electro-reduction processes were investigated and the products were characterized. The results show that the molten salt electro-reduction process can be used to produce nickel, copper and nickel-copper alloy directly from Ni3S2, Cu2S and converter matte precursors in molten CaCl2-NaCl, respectively. CaS would be formed as the intermediate compound during the electro-reduction process, and then the formed CaS can be gradually decomposed and removed with the increase of the electrolysis time. The experimental results show that the molten salt electro-reduction process has the potential to be used for the reduction of sulfide minerals in molten CaCl2-NaCl.展开更多
基金supported by the National Foundation of Natural Science of China
文摘A novel method is proposed to enhance the gasification and removal of copper from molten steel by adding ammonium salts or urea into molten steel under normal pressure.The decopperization experiments were conducted in a molybdenum-wire resistance furnace at 1 873 K.The copper content of about 400 g of a mild steel was reduced from 0.49%(mass fraction,the same below) and 0.51% to 0.31% and 0.38% using 0.7 g of NHC1 and 0.5 g of(NH)COrespectively,while the copper content of the molten steel was reduced from 0.61%to 0.56% using 2.00 g of NHCONH.
文摘In this study,for the first time,direct copper production from copper sulfide was carried out via direct electrochemical reduction method using inexpensive and stable molten borax electrolyte.The effects of current density(100–800 mA/cm^2)and electrolysis time(15–90 min)on both the cathodic current efficiency and copper yield were systematically investigated in consideration of possible electrochemical/chemical reactions at 1200℃.The copper production yield reached 98.09%after 90 min of electrolysis at a current density of 600 mA/cm^2.Direct metal production was shown to be possible with 6 kWh/kg energy consumption at a 600 mA/cm2 current density,at which the highest current efficiency(41%)was obtained.The suggested method can also be applied to metal/alloy production from single-and mixed-metal sulfides coming from primary production and precipitated sulfides,which are produced in the mining and metallurgical industries during treatment of process solutions or wastewaters.
文摘A novel method has been proposed to remove copper from molten steel by adding the compounds of hydrogen and nitrogen into the melt at normal pressure. Feasibility experiments were carried out in Mo-wire resistance furnace at 1600℃. The copper content of about 400 g 45 steel were reduced from 0.60% and 0.57% to 0.41% and 0.51% with 3.25g and 1.20 g NH_4Cl respectively, while the copper contents of about 300 g steel melt were reduced from 1.15% and 0.61% to 0.90% and 0.56% with 4.10 g and 2.00 g NH_2CONH_2. These results indicate that the proposed method is very promising to be put into practical and worthwhile of further study.
文摘The electrochemical behaviour of copper electrode in molten NaCl-KCl-LaCl_3 has been investigated.The La-Cu alloy is formed at first and then the metallic lanthanum is deposited when the La^(3+)is reduced on the copper electrode.The technological conditions of preparing La-Cu alloy by consumable cathode have been dis- cussed.The La-Cu alloy contained lanthanum over 90wt% was obtained.The composition of alloy was LaCu_2 and La.The current efficiency was 85% and the recovery of lanthanum was near 90%.
文摘The electrochemical behaviour of Y ̄(3+) and Ba ̄(2+) on platinum and copper electrode in molten YF_3(70 wt% )-NaF (20 wt%)-CaF_2(10 wt%) has been studied by means of cyclic voltammetry. discharge curve and so on. The Y-Ba-Cu alloy is obtained by fused salt electrolysis with molten YF_3-NaF-CaF_2 as electrolyte and Y_2O_3 and BaO as raw materials. Graphite cell acted as an anode and copper rod as consumable cathode. The molten bath temperature was 1193 K. Cathode current density was 20 A/cm ̄2. The contents of yttrium, barium and copper in alloy were about 20wt%, 9 wt% and 71 wt% respectively. Yttrium recovery efficiency was 90 wt%. The current efficiency was 70%~80 %.
基金the National Science Foundation of China under the contract No. 59874005.]
文摘The copper contents and its existing forms in the slags during the slag-making stage of Peirce-Smith converters in Guixi Smelter, Jiangxi Province, China have been investigated. The investigation was based on plant trials with the corresponding thermodynamic calculations and kinetic considerations. From the plant data, the total copper content in the slags was in the range of 2% to 8% (mass fraction). The mechanical entrainment of matte drops has been found to be the main cause of the copper loss. The suspension index, defined as the ratio of the mass fraction of copper in suspended matte drops in the slag to that in bulk of the matte phase, has been adopted to quantify the matte entrainment. The values of this parameter estimated in this work have been found mainly within a range of 2.5%-8.0%. The Fe3O4 content in the slag has been estimated to be the most important factor, among others, influencing the separation of slag with matte and, consequently, the copper loss from the slag.
基金This research was financially supported by the project KJCXGC-01 of Northwest Normal University, China.
文摘Solid liquid extraction of copper ion (I) with 2, 9-dimethyl-1, 10-phenanthroline (neo-cuproine, DMP) into molten naphthalene followed by chloroform spectrophotometric determination has been studied experimentally. The ternary complex Cu(I)-DMP-ClO4 was extracted quantitatively into molten naphthalene in the range of pH from 5 to 6 at 85 C-. Absorbance was spectrophotometrically determined at 459 nm against the reagent blank after the solid naphthalene layer was anhydrously dissolved in chloroform. Beer's law is obeyed over a concentration range of 0.5-70 mug/mL. The molar absorptivity and Sandell's sensitivity are 1.0x10(4) L/(mol(.)cm) and 0.0099 mug(.)cm(2) respectively. In addition, the various conditions on determination and the interference of coexisted ions were discussed, and the method was applied to the determination of copper ion both in tea samples and cadmium sulfate reagents. The results are in good agreement with those obtained by ICP AES method.
文摘The electrolytic production of nickel-copper alloy by electrochemical reduction of converter matte in molten salt has been investigated. The sintered solid porous pellets of Ni3S2, Cu2S and converter matte were electrolyzed at a voltage of 3.0 V in molten CaCl2-NaCl under the protection of argon gas at 700℃, respectively. The electro-reduction processes were investigated and the products were characterized. The results show that the molten salt electro-reduction process can be used to produce nickel, copper and nickel-copper alloy directly from Ni3S2, Cu2S and converter matte precursors in molten CaCl2-NaCl, respectively. CaS would be formed as the intermediate compound during the electro-reduction process, and then the formed CaS can be gradually decomposed and removed with the increase of the electrolysis time. The experimental results show that the molten salt electro-reduction process has the potential to be used for the reduction of sulfide minerals in molten CaCl2-NaCl.